Liver Blood Loss Research Articles

Portal vein clamping alone confers protection against hepatic ischemia–reperfusion injury via preserving hepatocyte function in cirrhotic rats

BackgroundChronic liver diseases always increase the risk of liver failure after hepatectomy. We aimed to explore the protective effect of portal vein clamping without hepatic artery blood control (PVC) on a cirrhotic rat liver that underwent ischemia and reperfusion. MethodsCarbon tetrachloride-induced cirrhotic rats were randomly assigned to four groups as follows: cirrhotic control, PVC, portal triad clamping (PTC), and intermittent portal triad clamping (IC). After 45 min of portal vascular clamping, hepatic injury and liver function were investigated by assessing the 7-d survival rate, liver blood loss, serum alanine aminotransferase, liver tissue malondialdehyde, liver tissue adenosine triphosphate, indocyanine green retention rate, and morphology changes of the rat liver. ResultsThe 7-d survival rates in the PVC and IC groups were much higher than in the PTC group. The PVC group had more liver blood loss during the hepatectomy than the PTC group, but had much less than the cirrhotic control group (P < 0.01). In addition, there were no differences between the IC group and PVC group. The PVC rats had a significantly higher adenosine triphosphate level in the liver tissue and a markedly lower indocyanine green retention rate than the PTC and IC rats (P < 0.05). At 1, 6, and 24 h after reperfusion, the alanine aminotransferase and malondialdehyde levels in the PTC group were much higher than those in the PVC and IC groups (P < 0.05). Based on the histopathologic analysis, hepatic injury in the PVC and IC groups were similar but less prominent than in the PTC group. ConclusionsAlthough both PVC and IC can confer protection against hepatic ischemic–reperfusion injury in cirrhotic rats, the PVC method is more efficient in preserving the energy and function of hepatocytes than the IC method, suggesting better prognosis after hepatectomy.

Preserving Hepatic Artery Flow During Portal Triad Blood Inflow Occlusion Reduces Liver Ischemia-Reperfusion Injury in Rats

Temporary portal triad clamping (Pringle maneuver) during liver resection can reduce intraoperative blood loss, but also correlates with liver ischemia and reperfusion (I/R) injury. The hepatic artery supplies 20%-30% blood but more than 50% O(2) to the liver. In this study, we explored if preservation of hepatic artery flow when performing portal triad blood inflow occlusion could reduce liver I/R injury while not increasing the blood loss. Three groups of rats were created: group SO (sham operation), group OPT (occlusion of portal triad under portal blood bypass), and group OPV (occlusion of portal vein under portal blood bypass). Blood flow was occluded for 90, 100, 110, and 120 min before reperfusion. Liver I/R injury was assessed by measuring the survival of rats within 7 d after operation, liver blood loss, serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), liver tissue malondialdehyde (MDA), and Na(+)-K(+)-ATPase, and liver histology. The 7-d survival of rats in group OPV was higher than in group OPT. The safe tolerance limit was 90 min for group OPT and 110 min for group OPV. Liver blood loss in group OPT and OPV were significantly less than in group SO. However, no significant difference was observed in the amount of blood loss between group OPT and group OPV. The group OPV had significantly lower ALT, AST, and MDA values on the first hour and first day post-reperfusion than in group OPT. The Na(+)-K(+)-ATPase activity in OPV group was significantly higher than in group OPT 1 h post-reperfusion. Hepatocyte injury was significantly less in group OPV than in group OPT on histopathology. These data indicate that continuously clamping the portal vein while preserving the hepatic artery did not increase blood loss significantly in a rat liver I/R model, however this maneuver induced less liver I/R injury. It is therefore suggested that preserving hepatic artery inflow during portal triad bloodinflowocclusion might become an alternative maneuver in liver surgery due to its ability to extendthesafe tolerant time limit in normothermic hepatic ischemia.